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Benjamin A Herman

Publications and source records attributed to Benjamin A Herman.

3 recordsLinked to original sources
PubMed2003

Computerized tomographic colonography: performance evaluation in a retrospective multicenter setting.

BACKGROUND & AIMS: No multicenter study has been reported evaluating the performance and interobserver variability of computerized tomographic colonography. The aim of this study was to assess the accuracy of computerized tomographic colonography for detecting clinically important colorectal neoplasia (polyps >or=10 mm in diameter) in a multi-institutional study. METHODS: A retrospective study was developed from 341 patients who had computerized tomographic colonography and colonoscopy among 8 medical centers. Colonoscopy and pathology reports provided the standard. A random sample of 117 patients, stratified by criterion standard, was requested. Ninety-three patients were included (47% with polyps >or=10 mm; mean age, 62 years; 56% men; 84% white; 40% reported colorectal symptoms; 74% at increased risk for colorectal cancer). Eighteen radiologists blinded to the criterion standard interpreted computerized tomography colonography examinations, each using 2 of 3 different software display platforms. RESULTS: The average area under the receiver operating characteristic curve for identifying patients with at least 1 lesion >or=10 mm was 0.80 (95% lower confidence bound, 0.74). The average sensitivity and specificity were 75% (95% lower confidence bound, 68%) and 73% (95% lower confidence bound, 66%), respectively. Per-polyp sensitivity was 75%. A trend was observed for better performance with more observer experience. There was no difference in performance across software display platforms. CONCLUSIONS: Computerized tomographic colonography performance compared favorably with reported performance of fecal occult blood testing, flexible sigmoidoscopy, and barium enema. A prospective study evaluating the performance of computerized tomography colonography in a screening population is indicated.

Colonic Neoplasms↗
PubMed2002

Decreased laboratory testing for lecithin-to-sphingomyelin ratio and phosphatidylglycerol after fetal lung maturity assessment from lamellar body count in amniotic fluid.

The objectives of this study were to do inexpensive lamellar body count (LBC) in amniotic fluid, to do statistical analysis to evaluate cutoff values for fetal lung maturity (FLM) and fetal lung immaturity (FLI), to derive a threshold for obtaining a lecithin-to-sphingomyelin (L/S) ratio and phosphatidylglycerol percentage (%PG), and to determine the potential cost savings to the hospital if they use this new method. Testing (LBC, L/S ratio, and %PG) was done on 123 specimens of amniotic fluid. Receiver operating characteristic (ROC) curve, discriminant, linear regression, chi2, and cost analyses were used to evaluate the laboratory and financial parameters. Lamellar body counts of greater than 41,500 (Coulter MAXM: sensitivity, 90.5%; specificity, 87.7%; positive predictive value, 79.2%; negative predictive value, 94.7%) and greater than 32,000 (Coulter Gen.S: sensitivity, 90.5%; specificity, 85.2%; positive predictive value, 76.0%; negative predictive value, 94.5%) were the best threshold for biochemical FLM. Similarly, LBC of less than 24,000 (MAXM: sensitivity, 78.6%; specificity, 100%; positive predictive value, 100%; negative predictive value, 90.0%) and less than 21,000 (Gen.S: sensitivity, 71.4%; specificity, 100%; positive predictive value, 100%; negative predictive value, 87.1%) provided the best statistical cutoff for biochemical FLI from discriminant analysis. The authors concluded that FLM and FLI can be predicted with reasonable accuracy from LBC in amniotic fluid specimens. The expensive and not easily accessible L/S ratio and %PG can then be done only in cases in which LBC indicates transitional FLM. A cascade approach results in 86% savings to the hospital if the L/S ratio and %PG are not sent to a reference laboratory.

Adult↗